1. Field of the Invention
The present invention relates to an axial gap type motor.
Priority is claimed on Japanese Patent Application No. 2006-325397, filed on Dec. 1, 2006, and Japanese Patent Application No. 2007-223053, filed on Aug. 29, 2007, the contents of which are incorporated herein by reference.
2. Description of Related Art
Conventionally, an axial gap type permanent-magnet synchronous apparatus having a rotor and a pair of stators opposed to each other and holding the rotor therebetween from both sides of a rotation axis is known. In the permanent-magnet synchronous apparatus, a magnetic flux loop is formed via the pair of stators with respect to a magnetic field flux by a permanent magnet of the rotor (refer to Japanese Unexamined Patent Application, First Publication No. H10-271784, and Japanese Unexamined Patent Application, First Publication No. 2001-136721, for example).
The above conventional permanent-magnet synchronous apparatus has a problem in which practicable revolutions and torque are limited to certain values by generation of prescribed back electromotive voltage in accordance with an induced voltage constant in high-revolution region since the induced voltage constant is a fixed value according to a construction of the rotor having the permanent magnet or the like.